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Buick Lucerne: Real World MPG



  • Taralee, you might have something wrong with yours. My V-6 has plenty of power and torque to get me out of danger. It seems to have more than the Lesabre it replaced. The power of this car exceeds my nerve. The dead spot in the gas pedal is barely noticeable when you are on a highway and are on slight inclines and trying to hold a steady speed without using the cruise control.
  • taraleetaralee Posts: 13
    I agree with you totally. There is something wrong, but the dealership and Buick won't address it because they can't prove it by hooking it up to the diagnostic computer and finding a CODE for the problem....It won't code.
  • imidazol97imidazol97 Crossroads of America: I70 & I75Posts: 18,054
    What I would try is taking the car out on a lonely road and driving it in 1st and seeing if it has a lot of power when you step on it at slow speeds--say 20. Then try in 2nd and floor it at 35 or 40 in that gear. Then driving in 3rd at 50 and floor it quickly. Then floor it slowly after the car is cruising in 3rd and the torque convert clutch is locked up.

    Then leave the car in OD and try flooring at different speeds and see what gear it shifts down into and how the power feels at different speeds. All I can figure is the transmission didn't do a full downshift to the lowest gear for full power when you accelerated to pass the truck because you may have pushed down slowly on the pedal and it didn't perceive that a request for lots of power was being made. I'm picturing you going at 45 or 50 and attempting a pass, right?

    Be clear that I'm not blaming you for not doing something the way the car wanted. I'm trying to help you figure out what the car wants. There have been lots of posts on a Toyota discussion about quirky communication between transmissions and software and engines in certain cars. I have my 3rd leSabre with the 3800 and can't imagine not having enough power to pass. It's not a 455 cu. in. V8 engine like used to be available but it surprises me occasionally when I punch it with the downshifts and the power it comes up with because I usually drive it very, very tamely. I'm not going to pass semi trucks on 2 lane roads at 65 mph with an oncoming car 1/2 mile away as I start to pull out, but it provides more than enough power for me.

    Good luck getting it straightened out.
  • taraleetaralee Posts: 13
    Thank you for your help. I will get my hubby to ride with me and do what you suggested and post my findings.
  • pdg5710pdg5710 Posts: 1
    Can anyone tell me if there is or should be any significant difference in mileage with the traction control on/off? My 07 CXL doesn't come close to my 02 LeSabre - same engine.
  • I've never switched the traction control off in my '06 CX so I really couldn't say ... but I'm getting excellent mileage as it is anyway. 30+ on the highway, 26 overall city/highway/winter/summer. The variation in mileage that people are reporting is a mystery to me. My Lucerne gets better mileage than my '01 Malibu with a 3.1L V-6. Go figure.
  • hjw1hjw1 Posts: 17
    Our 07 Lucerne CXL has just over 8,000 miles on it, and we finally took it on a road trip this past weekend. We traveled 668 miles that were mostly interstate and rural highway. The DIC indicated 27.1 MPG, but my calculated MPG was 28.3. I carefully topped off the tank before, during, and after our trip, so I think that my calculated 28.3 is more accurate.

    My wife drives our Lucerne 3 miles to work. With the daily short trips in the city, our mileage is 17 - 18.
  • On November 1st., I bought a new 2007 Lucerne CXL V-8 from Perrine Buick, Pontiac, GMC, Hummer in Cranbury, New Jersey. I immediately drove it home to Florida, approximately 1200 miles. It performed flawlessly. The car has a 4.6 liter Northstar V-8; mileage ranged from 25-26.5 MPG with 2 passengers and a small amount of luggage. This was all on I-95, the speed limit being anywhere from 55-70 MPH depending upon which state and whether there was road construction going on. I thought this was good mileage considering the larger engine. I am sure that the V-6 would have given a couple more miles per gallon, but it would not be worth it when you compare the engine noise, strain, etc., that you would have to endure with the V-6. The V-8 has the torque and power to move the care effortlessly. It is a quiet engine and made for an extremely nice ride.
  • lane2lane2 Posts: 28
    Glad you are having good luck with your V8. I just purchased a leftover 2007 CXL V8 and would like to know what octane gas you are using. The dealer started me off with a tank of 87 octane and I haven't noticed any pinging and it seems to have plenty of power. Getting ready to take a trip to the mountains and would like to get the best mpg possible. Bought the car for my wife because she has a bad back and needed as many seat adjustments as possible.
  • imidazol97imidazol97 Crossroads of America: I70 & I75Posts: 18,054
    I'd put in a tank of a quality brand name premium and see if you notice any difference in the driveability. You probably will pay the same per mile; slight increase in gas mileage and a slight increase in cost per gallon at fillup.

    Myself, I'd just put in the plus grade and be happy. But I am a gentle driver.
  • lane2lane2 Posts: 28
    Thanks. What octane were you using on your trip? Would like to try a tank of the same octane to for the trip up to the mountains and if I get the mpg like you did, not bother checking the other octanes for efficiency.
  • lane2lane2 Posts: 28
    Since I had a full tank of 87 octane, tried all 87 octane for this trip. Had a high of 26 mpg up and back home and a low of 19.8 mpg in the snow in the mountains, very slow up and down. Total of about 950 miles. Very pleased with the performance, no pinging , and plenty of power. Just me and my wife but LOTS of luggage plus golf clubs. Guess I will try 93 octane for the next trip and see if there is any difference in mpg.
  • Just bought a used 2008, 14K miles, CXL as a Certified Used Car from the dealership and love this car. My previous one was a 1999 Regal LS, and I loved it too. The Regal was the same engine and got 24MPG. My old car broke down for the very last time just before Christmas. I did not have many choices for replacements, because dealers have kept inventories very low. My new Lucerne is only getting about 18MPG. I live in central west NJ, and the nearest gas station and town is 5 miles away in any direction. I drive 50 miles round trip to work, but have only used the car twice so far to get there. Most driving is county roads at around 50mph and highway at 70mph. What can I do to increase MPG? I have heard premium gas, new K&N filters, fuel system cleaner, and tire pressure. Is there anything else I should seriously consider?
  • oldguy8oldguy8 Posts: 12
    I am satisfied with my mileage on my V6 on a loaded trip to Florida I averaged 27mpg think this would have been better had I realized this engine actually gets better mileage at 70 than at 60, the last fill up was at 70 on the interstate and was 28.6 Actual, I find the computer will be high sometimes and low others and right on at times. 17-20 normal for in town driving depends on the stop lights and the duration of those lights.
  • I worked on the 3800 line at Buick until the last one was built which was Friday, August 22, 2008 at about 12:00pm. I ran the dept that checked each engine for faults and leaks. If an engine was rejected, I analizied the computer info and preformed the basic repairs. Sometimes the decision was a bad cylinder bore or maby a lifter bore too tight causing vibration or too loose causing an oil pressure problem. Many situations.
    The answer to the question on oil used during assembly is 10w30.
    Remember that in a mass production situation there are many variables which could result in varying fuel millage. All the testing equipment was computer controled, but also had tolerances for the 12 different tests. If an engine was pushing the limits of one or more of the tests and the computer accepted these it sent the engine out. Each engine has its own personality which was developed through machining, parts, and the assembly process and a combination of these could lead to posible lower fuel millage. Any questions just ask and maybe I can shed some light.
  • kenb757kenb757 Posts: 149
    Does GM use a special break-in oil or additve for the initial factory fill, or is it the over-the-counter (Goodwrench?) stuff? My DTS got about 2 mpg better (at 20 mpg) than my Lucerne Super, but I think it has more to do with tuning and the final drive ratio, than with other inherent differences in the Northstar V-8s.
  • buicks5buicks5 Posts: 20
    If you happen to ever see this reply, then please note that I have a 2000 Park Ave Ultra with the supercharged 3.8. This supercharged 3.8 now has 204,000 miles on it and is the best running car and engine of any vehicle i have ever owner at any miles on a vehicle. It does use a tiny amount of oil (1qt at 2500-3500 miles), past the rear valve cover, which is normal. GM replaces the gaskets on other applications, because of possible fire from dripping oil, but not an issue on this car.

    The supercharger uses a tiny about of oil at about 5,000 miles; maybe 1/4-1/2 pint. Engine starts instantly, does not smoke under any conditions, and pulls hard with good acceleration. I have always used Mobil 1 10/30 with Mobil 1 filter (extra fine filtration).

    The water pump is still good and tight and the dealer says the timing chain generally does not require replacement, even at high miles...a rarity.

    Fuel economy is 24-25mpg at 75-80m mph and 29-31mpg at 55-60mph. Commuting at 17 miles one way is about 21-22mpg.

    Shame that GM found it necessary to cease production. I had a 3.8 in a Toronado and it was also bulletproof. What a terrific engine!
  • I recently purchased a 2007 Lucerne CXL with 3800 series II and am only getting 22 MPG highway. This is very surprising to me as I had two Park Avenues, 1996 and 1999 with that engine and consistently got 29 MPG highway. I was expecting similar or better with the smaller Lucerne.
    This car olnly has 17,000 miles and everything seems to run and shift fine. I had the oil changed and tires rotated right after I got it 2 months ago.
    Any suggestions for trying to increase the MPG on highways?
    I appreciate your thoughts.
  • gmcustsvcgmcustsvc Posts: 4,057
    Hi Michaeldm,

    Some tips for improving your vehicle fuel economy include using Drive (D) as opposed to 2nd and 3rd gear; letting your vehicle heat up in cold temperatures; making sure no indicator lights are on your vehicle (particularly the Check Engine Light). Also remember that different driving conditions produce different fuel economies (ex. freeway driving versus city driving). Also try resetting your AVG ECONOMY on the display, as this allows for a more accurate reading of the average fuel economy. Please let me know if you have any other questions.

    Amber N.
    GM Customer Care
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